JPS58165470A - Conference telephone system - Google Patents

Abstract

PURPOSE:To reduce the number of relay lines occupied with the connection to the conference, by providing a means setting the connection to the conference among subscribers to a relay exchange, in an automatic exchange network. CONSTITUTION:A relay exchange Px is provided with a conference trunk CFT. In executing the prescribed operation from a subscriber A1 to A2, channels C12 and C13 are released in the relay exchange Px, C11 and C14 are set, a relay trunk PVT3 is connected to an outgoing register trunk OGT, a PVT4 is connected to the trunk CFT. When the A1 dials a prescribed specific number and the number of A3, after a channel C19 is set, a PT5 and an OST are connected, the number of A3 from the OST is transmitted, the channel to the A3 via a relay line L3-1 and an exchange P3 is set, the channels C13 and C19 are released, C15 and C16 are set, A1 and A3 are connected. When the subscriber A1 executes the prescribed operation, the channels C15 and C16 are released, C17 and C18 are set, the PVTs 3 and 5 are connected to the conference trunk CFT and the operation is finished.

Description

DETAILED DESCRIPTION OF THE INVENTION la) Technical Field of the Invention The present invention relates to a conference telephone system, particularly an automatic switching system comprising a plurality of subscriber exchanges accommodating subscribers and a relay exchange connecting the subscriber exchanges to each other. Concerning the conference telephone system in the network.

Prior Art and Problems It is known that an automatic switching system not only connects a pair of accommodated subscribers to each other, but also connects any three subscribers to each other for a so-called conference call. In particular, it is not uncommon for subscribers belonging to a plurality of subscriber exchanges constituting the automatic switching network to conduct such conference calls.

FIG. 1 is a diagram showing an example of this kind of conventional automatic switching network equipped with a conference telephone function. In FIG. 1, a plurality of subscriber exchanges Pl to Pn are connected to subscribers AI to A, respectively.
An automatic switchboard SW accommodating n and a conference trunk CFT are provided.

Further, each subscriber exchange P1 to Pn is connected to a trunk exchange Px by trunk line groups Ll to Ln, and the subscribers A1 to An accommodated in each subscriber exchange Pl to Pn are exchanged by the trunk exchange Px. Connected. FIG. 2 is a diagram showing an example of the conventional conference telephone system shown in FIG. In FIG. 2, a network NW, a central control unit CC1, an originating register trunk ORT, an originating cededer trunk O3T, and trunk line trunks PVTI and PVT2 that constitute the automatic exchange SW of the subscriber exchange Pi are shown. It is assumed that a subscriber A1 accommodated in the subscriber exchange P1 holds a conference call with a subscriber A2 accommodated in the subscriber exchange P2 and a subscriber A3 accommodated in the subscriber exchange P3. For the first time, the subscriber AI makes a call, is connected to the calling register trunk ORT via the communication path CI of the network NW, and then dials the telephone number of the subscriber A2, and then the subscriber AI makes a call in the network NW by a known process. Communication path C2, trunk line trunk PVTI, trunk line Ll-1 in trunk line group Ll. It is connected to subscriber A2 via trunk exchange PX, trunk line L2-1 in trunk line group L2, and subscriber exchange P2.

After subscriber A1 tells subscriber A2 that a conference will be held,
When a predetermined operation (for example, hooking) is performed, the central control unit CC in the subscriber exchange Ll releases the communication path C2 set in the network NW, sets up the communication path C1, and connects the subscriber A1 with the communication path C1. The outgoing register trunk O
Connect to RT.

After the subscriber AI hears the second dial tone returned from the calling register trunk ORT, it dials the predetermined tokusemi number and subscriber A3's phone number for the conference call. and □, the central controller CC sets up a communication path C3 within the network NW and connects the trunk trunk PVT.
2 and the originating sender trunk OS 1', the telephone number of the subscriber A3 is sent from the originating sender trunk O3T, and the telephone number of the subscriber A3 is sent from the originating sender trunk O3T to the trunk line Ll-2 in the trunk group Ll, the trunk exchange Px, and the trunk line L3 in the trunk group L3. A connection path to subscriber A3 is set up via trunk line L3-1 and subscriber exchange P3,
Furthermore, call paths ci and C3 are released, call paths C4 and C5 are set up, and subscriber AI
and subscriber A3. Note that the subscriber A2 is connected to the conference trunk CFT via the call path C6 set within the network NW by the central M controller CC, and is listening to the hold tone. When subscriber A1 notifies subscriber A3 that a conference is to be held and then performs a predetermined operation (for example, hunking), conference trunk CFT stops sending hold music to subscriber A2, and - enters A1, A2. and A3 are connected. As a result of the above, subscriber AI sends the desired conference call to subscriber A2t, ? and A3. □ As is clear from the above explanation, in the conventional conference telephone system, subscribers AI, A2, and A3 participating in the conference
are connected by a conference trunk CFT provided in the subscriber exchange P1 to which the host subscriber AI belongs.

Therefore, in order to connect subscriber A2 belonging to subscriber exchange P2 and subscriber A3 belonging to subscriber exchange P3, trunk lines L1-1 and Ll-2 in trunk line group Ll are occupied. becomes. Furthermore, when a large number of subscribers belonging to subscriber exchanges P2 to Pn participate in the above-mentioned conference, the number of trunk lines occupied for the conference in trunk line group Ll increases, and trunk line group LL This will put pressure on the volume of calls that go through the network. -゛(C) Object of the Invention The object of the present invention is to eliminate the drawbacks of the conventional conference telephone system as described above, and to provide a system for monopolizing conference calls by establishing conference connections between subscribers who belong to a plurality of local exchanges in a distributed manner. The goal is to reduce the number of trunk lines as much as possible.

td) Arrangement of the invention The object is to provide a plurality of subscriber exchanges accommodating subscribers;
In an automatic switching network consisting of a relay exchange that connects the subscriber exchanges with each other, 'achieved by providing means for setting up a conference connection between the subscribers belonging to the plurality of subscriber exchanges in the relay exchange. be done.

(el　Embodiments of the invention An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 is a diagram illustrating an example of an automatic switching network equipped with a conference function according to an embodiment of the present invention, and FIG. 4 is a diagram illustrating a conference telephone system according to an embodiment of the present invention in FIG. 3. . Note that the same reference numerals indicate the same objects throughout the figures. Also in FIG. 3, the automatic switching network includes subscriber exchanges Pl to Pn accommodating subscribers A1 to An, respectively, subscriber exchanges P1 to Pn, and trunk line groups Ll to Pn, respectively.
It consists of a relay exchange Px connected to a relay exchange Px. However, in order to realize conference connections across subscribers A1 to An belonging to a plurality of subscriber exchanges Pl to Pn, a conference door rank CFT is provided in the relay exchange Px. Next, as in FIG. 2, subscriber A1
The process of holding a meeting in which 2 and A3 participate will be explained in the 4th session.
This will be explained using figures. In Figure 4, the trunk exchange Px
The network NW, central control unit CC1, outgoing register trunk ORT, outgoing sender trunk OST, and trunk line trunks PVT3 to PV that constitute the automatic exchange SW of
T5 is shown. First, when the subscriber Al makes a call and dials the telephone number of the subscriber A2, in a known process, the trunk 1-1 of the trunk exchange P1 in the trunk group Ll of the subscriber exchange P1, the trunk trunk PVT3 of the trunk exchange Px, and the network NW
Channels C12 and C13 within trunk trunk PVT
4. Connected to subscriber A2 via trunk line 2-1 in trunk line group L2 and subscriber exchange P2. After subscriber Al informs subscriber A2 that a conference will be held, when a predetermined operation (for example, hooking) is performed, trunk exchange P
The central controller CC in x is 0.
6 call paths configured. 1□ and C13, set up communication paths C1l and C14, and subscriber A
The trunk line trunk P, VT3 leading to subscriber A2 is connected to the originating register trunk ORT, and the second tone sent by the originating register trunk ORT is made to be heard by the subscriber A1, and the trunk line trunk PVT4 leading to subscriber A2 is connected to the originating register trunk ORT. Trunk C
FT and allows subscriber A2 to listen to the hold tone sent by the conference trunk CFT. When subscriber A1 hears the second dial tone and dials the special number predetermined for the conference call and the telephone number of subscriber A3, the central controller CC sets up a call path C19 in the network NW. After connecting trunk trunk PVT5 and originating sender trunk O3T, subscriber A3 is connected from originating sender trunk O3T to subscriber A3.
and transmits the telephone number of trunk line L3- in trunk line group L3.
1 and subscriber exchange P3, a connection path is established for subscriber A3, and communication paths C13 and C19 are released, communication paths C15 and C16G are established, and subscriber AI and subscriber A3 are connected. □Subscriber A1 is subscriber A3
When a predetermined operation (for example, meeting) is performed after notifying the conference that a conference will be held, the central control unit CC releases communication paths C15 and C16 set within the network NW and uses communication paths C17 and C16. Set C1B,
Trunk trunk PvT3 leading to subscriber AI and trunk trunk PvT5 leading to subscriber A3 are connected to conference trunk CF.
Furthermore, the transmission of holding tone to subscriber A2 from the arrangment trunk CFT is stopped. As a result, subscriber A
1, A2 and A3 are conference-connected via the conference trunk CFT, and subscriber A1 can initiate the desired conference call.

As is clear from the above description, according to this embodiment, subscribers A1. , A2 and A3 are conference-connected by a conference trunk CFT provided in the transit exchange Px. Therefore, the trunk line groups LISL2 and L3 connecting the trunk exchange Px and each local exchange PL, P2, and P3, respectively, each subscriber exchange P1.22 and P
Only trunk lines L1-1, L2-1 and L3-1 necessary for connecting participating subscribers A1, A2 and A3 belonging to No. 3 are occupied.

It should be noted that FIGS. 3 and 4 are only one embodiment of the present invention, and for example, holding a conference is not limited to subscriber AI belonging to subscriber exchange P1, but also to other subscriber exchange P2. Although it is also possible to use any subscriber belonging to Pn to Pn, the effect of the present invention does not change in either case.

Further, the number of participants in the conference is not limited to three, and the effects of the present invention do not change even in the case of any other number of participants. Further, the configuration of the transit exchange Px is not limited to that shown in the drawings, and many other modifications may be considered, but the effects of the present invention will not change in any case.

(f) Effects of the Invention According to the present invention, in the automatic switching network, the number of occupied trunk lines is minimized by conference connections established between subscribers who belong to a plurality of subscriber exchanges in a distributed manner. This allows the relay line group to be used effectively.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an example of an automatic switching network equipped with a conventional conference telephone function, Fig. 2 is a diagram showing an example of the conventional conference telephone system in Fig. 1, and Fig. 3 is an example of an embodiment of the present invention. Figure 4 showing an example of an automatic switching network equipped with a conference function by
The figure is a diagram illustrating a conference telephone system according to an embodiment of the present invention in FIG. 3. In the figure, AI to An are subscribers, PI to Pn are subscriber exchanges, Px is a transit exchange, SW is an automatic exchange, and C
FT is a conference trunk, Ll to Ln are trunk line groups, Ll-
1, Ll-2, L2-1 and L3-1 are trunk lines, NW
is the network, CC is the central controller, ORT is the outgoing register trunk, O3T is the outgoing sender trunk, PVT
I to PVT5 indicate trunk line trunks, and C1 to C6 and C11 to C19 indicate communication paths. 10th Figure 1 Figure 2 Figure 1 Figure 3 Figure 4 p

Claims (1)

[Claims] In an automatic switching network consisting of a plurality of subscriber exchanges accommodating subscribers and a relay exchange that connects the subscriber exchanges with each other, a conference connection is established between the subscribers belonging to the plurality of subscriber exchanges. The conference telephone system is characterized in that the relay exchange is provided with means for doing so.